This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A059665 #10 Sep 08 2022 08:45:03
%S A059665 433,919,1423,1999,2017,2143,2287,2791,2953,3457,3889,3943,4177,4519,
%T A059665 4663,5113,5167,6679,6967,8713,9631,9649,9721,10009,11287,11863,12241,
%U A059665 12583,12799,13177,13591,15913,16057,16111,16561,16921,17551,18127
%N A059665 Primes p such that x^54 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.
%H A059665 Vincenzo Librandi, <a href="/A059665/b059665.txt">Table of n, a(n) for n = 1..389</a>
%t A059665 Select[Prime[Range[PrimePi[20000]]], !MemberQ[PowerMod[Range[#], 54, #], Mod[2, #]] && MemberQ[PowerMod[Range[#], 6, #], Mod[2, #]] &] (* _Vincenzo Librandi_, Sep 21 2013 *)
%o A059665 (Magma) [p: p in PrimesUpTo(20000) | not exists{x: x in ResidueClassRing(p) | x^54 eq 2} and exists{x: x in ResidueClassRing(p) | x^6 eq 2}]; // _Vincenzo Librandi_, Sep 21 2012
%Y A059665 A000040, A040992, A040993, A049550, A059666, A059664.
%K A059665 nonn,easy
%O A059665 1,1
%A A059665 _Klaus Brockhaus_, Feb 04 2001